Rory having three cancers by age sixteen and the family history of prominent cancer diagnoses prompted Miranda Bailey to look for a genetic reason. She discovered a mutation of the P53 gene and concluded that the family carried Li-Fraumeni Syndrome, which affects their bodies' ability to regulate cell growth.

Rory became unresponsive and wasn't breathing properly, so she was rushed into surgery. Despite the doctors' best efforts, Rory bled out into her chest and died. When the doctors came to tell the Williams family, they were distraught and it prompted Ariel to ask the doctors if she also had Li-Fraumeni, which she did.

Rory got along well with her sister, Ariel. Ariel was with her when she became unresponsive, prompting the surgery in which she died. After her death, her sister said she'd always wanted to be like her.